将“ true”（JSON）转换为等效于Python的“ True”

Question

我最近使用的Train status API(has_arrived, has_departed)在JSON对象中添加了两个额外的键值对，这导致我的脚本崩溃。

这是字典：

{
"response_code": 200,
  "train_number": "12229",
  "position": "at Source",
  "route": [
    {
      "no": 1,
      "has_arrived": false,
      "has_departed": false,
      "scharr": "Source",
      "scharr_date": "15 Nov 2015",
      "actarr_date": "15 Nov 2015",
      "station": "LKO",
      "actdep": "22:15",
      "schdep": "22:15",
      "actarr": "00:00",
      "distance": "0",
      "day": 0
    },
    {
      "actdep": "23:40",
      "scharr": "23:38",
      "schdep": "23:40",
      "actarr": "23:38",
      "no": 2,
      "has_departed": false,
      "scharr_date": "15 Nov 2015",
      "has_arrived": false,
      "station": "HRI",
      "distance": "101",
      "actarr_date": "15 Nov 2015",
      "day": 0
    }
  ]
}

毫不奇怪，我得到了以下错误：

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'false' is not defined

如果我没记错的话，我认为这是因为JSON响应中的布尔值是false/，true而Python可以识别False/
True。有什么办法解决吗？

PS：我尝试将的JSON响应转换has_arrived为字符串，然后将其转换回布尔值，结果发现True如果字符串中有任何字符，我总会得到一个值。我有点卡在这里。

Answer 1

尽管Python的对象声明语法与Json语法非常相似，但它们是截然不同且不兼容的。除True/true问题外，还有其他问题（例如，Json和Python处理日期的方式非常不同，而python允许单引号和注释，而Json不允许）。

解决方案不是尝试将它们视为同一事物，而是根据需要将它们从一个转换为另一个。

Python的json库可用于解析（读取）字符串中的Json并将其转换为python对象…

data_from_api = '{"response_code": 200, ...}'  # data_from_api should be a string containing your json
info = json.loads(data_from_api)
# info is now a python dictionary (or list as appropriate) representing your Json

您也可以将python对象转换为json …

info_as_json = json.dumps(info)

例：

# Import the json library
import json

# Get the Json data from the question into a variable...
data_from_api = """{
"response_code": 200,
  "train_number": "12229",
  "position": "at Source",
  "route": [
    {
      "no": 1, "has_arrived": false, "has_departed": false,
      "scharr": "Source",
      "scharr_date": "15 Nov 2015", "actarr_date": "15 Nov 2015",
      "station": "LKO", "actdep": "22:15", "schdep": "22:15",
      "actarr": "00:00", "distance": "0", "day": 0
    },
    {
      "actdep": "23:40", "scharr": "23:38", "schdep": "23:40",
      "actarr": "23:38", "no": 2, "has_departed": false,
      "scharr_date": "15 Nov 2015", "has_arrived": false,
      "station": "HRI", "distance": "101",
      "actarr_date": "15 Nov 2015", "day": 0
    }
  ]
}"""

# Convert that data into a python object...
info = json.loads(data_from_api)
print(info)

第二个示例显示True / true转换是如何发生的。还请注意对引号的更改以及如何删除注释…

info = {'foo': True,  # Some insightful comment here
        'bar': 'Some string'}

# Print a condensed representation of the object
print(json.dumps(info))

> {"bar": "Some string", "foo": true}

# Or print a formatted version which is more human readable but uses more bytes
print(json.dumps(info, indent=2))

> {
>   "bar": "Some string",
>   "foo": true
> }